I put a Demon 750 on my stumbling 440 last night.

Posted By: DAYCLONA

Re: I put a Demon 750 on my stumbling 440 last night. - 07/25/14 03:36 PM

Quote:

And now you know one of the reasons I don't use edelbrocks...

Totally agree...unless you rework the entire carb inside/out, the Eddys are POS

Re: I put a Demon 750 on my stumbling 440 last night. - 07/25/14 04:37 PM

well I have been running a eddy 600 or a 750 for the last 20 yrs. results did vary depending on the engine combo. all street duty daily drivers.

this past weekend I put a 20yr old 6210 spredbore mech double pumper/holley street dominator on.

2x 85 stepside 91 JY 318/whiplash roller cam/NV4500 5 speed/3.55sg 4000# daily driver.

WOWZERS! that thing woke up and made a big improvement in the lowend torque/drivabilty and flat out kicks in when going WOT.

feels stronger/smoother/ and picked up a couple MPG

think I will get a 3310 750cfm mech double pumper for the 88-440 truck and remove the edelbroke.

I don't recall WHY I went to edelbroke in the first place other than it was free??

I always thought holleys were nothing more than gas holes with poor mpg but I am seeing the light 20yrs later.

Posted By: Dcuda69

Re: I put a Demon 750 on my stumbling 440 last night. - 07/25/14 06:51 PM

Quote:

well I have been running a eddy 600 or a 750 for the last 20 yrs. results did vary depending on the engine combo. all street duty daily drivers.

this past weekend I put a 20yr old 6210 spredbore mech double pumper/holley street dominator on.

2x 85 stepside 91 JY 318/whiplash roller cam/NV4500 5 speed/3.55sg 4000# daily driver.

WOWZERS! that thing woke up and made a big improvement in the lowend torque/drivabilty and flat out kicks in when going WOT.

feels stronger/smoother/ and picked up a couple MPG

think I will get a 3310 750cfm mech double pumper for the 88-440 truck and remove the edelbroke.

I don't recall WHY I went to edelbroke in the first place other than it was free??

I always thought holleys were nothing more than gas holes with poor mpg but I am seeing the light 20yrs later.

A 3310 is a vac secondary carb. Regardless, a very good street carb on a big block

Oh and I agree with all the comments on the Edelbrocks...I've fought with a couple...then bolt on a Holley and DONE!!

Posted By: KillerBee

Re: I put a Demon 750 on my stumbling 440 last night. - 07/25/14 06:55 PM

Yep I got hypnotized years ago by a shiny new Edelbrock 1407 and foolishly replaced the good running Holley 750DP that was on the car.

After a few weeks of fighting with the off idle stumble and terrible performance I removed the shiny Edelbrock and sold it to a buddy with a 350 Chebbie and put the Holley back on, lesson learned....

Posted By: dogdays

Re: I put a Demon 750 on my stumbling 440 last night. - 07/25/14 07:05 PM

Let's not get into the usual carb wars.

The important thing about this post is that the Street Demon 750 bolted on and worked RIGHT OUT OF THE BOX!

I want one.

R.

Posted By: RobX4406

Re: I put a Demon 750 on my stumbling 440 last night. - 07/25/14 07:26 PM

Initial timing may play a big part in some stumbles. Not enough and it's worse.

Posted By: Steve Bryant

Re: I put a Demon 750 on my stumbling 440 last night. - 07/25/14 07:51 PM

I also applaud the fact there are bolt-on carb solutions out there that work! There is wisdom in buying something that works the first time. Thanks for sharing!

This year I managed to tame my Eddy into something that does not stumble. For me, it was time-consuming, somewhat more expensive and required several weeks of testing and tuning. I don't blame anyone for buying something out of the box that is better and works the first time and I certainly don't blame the Eddy owner. The problem is most certainly with the stock Eddy carbs.

Posted By: 6PACMAC

Re: I put a Demon 750 on my stumbling 440 last night. - 07/26/14 03:18 AM

Back in the day, I had a new Carter 750 Comp series AFB on my stock port 906 headed 67' GTX running 12.2-3s in the summer heat at the strip and idling like crap. My buddy brought along a untouched Holley 850dp, which we swapped on to the GTX. For the rest of the day the car ran 11.80s and would idle without dying like the Carter would.

Posted By: bee1971

Re: I put a Demon 750 on my stumbling 440 last night. - 07/26/14 05:19 AM

Quote:

Back in the day, I had a new Carter 750 Comp series AFB on my stock port 906 headed 67' GTX running 12.2-3s in the summer heat at the strip and idling like crap. My buddy brought along a untouched Holley 850dp, which we swapped on to the GTX. For the rest of the day the car ran 11.80s and would idle without dying like the Carter would.

Kind Of An Unfair Comparison , Wouldn't You Say

And The Carter Comp 750 Is 100 Times Better Then The Edelbrock 750 Series , And Most Will Say They Are The Same Carbs , Wrong Answer

I Think Most Know How Much I Love The Edelbrock 750 Series COUGH COUGH

However , Honestly The Edelbrock 800 Series AVS Are Pretty Damn Nice Carbs , And Work Well

Click On Link (Moparts Archives) And Look At The Dyno Numbers Comparing The Edelbrock 750 Along Side The Carter 750 Comp And Others

Then Read What He Has To Say About The Edelbrock 750 - Same Things I Have Been Preaching On This Website For Years , And At Times Getting Ripped For It

http://www.moparts.org/Tech/Archive/bb/25.html

Posted By: 6PACMAC

Re: I put a Demon 750 on my stumbling 440 last night. - 07/26/14 05:53 AM

Ya, maybe a little unfair size wise. The Holley had the full choke set up where as the Carter is choke less. Beside the performance increase with the Holley, the car would truly idle. The Carter's and Edelbrocks seem to have sloppier throttle shafts, as in they should be bushed. I think the slop hurts idle quality by allowing a slight vac leak.

Posted By: 2boltmain

Re: I put a Demon 750 on my stumbling 440 last night. - 07/26/14 04:18 PM

Its fascinating to hear about the Edelbrock 750 performer. Its an observation voiced by many- not just the mopar crowd. I realize the powers that be at Edelbrock just ignore the shortcomings but I wonder if they at least acknowledge their 750 could use a revision to make it as good as it can be- as good as the Carter 750 from which it is based. Im impressed that someone at Demon recognized the worth of the old Thermoquad and had the guts to bring an improved version of it to the market.

Posted By: RTDaddy

Re: I put a Demon 750 on my stumbling 440 last night. - 07/27/14 12:21 AM

Quote:

I've got a 440 with low idle vacuum that's always had Edelbrock carbs and an off idle stumble. I just converted it to a 4sp and the stumble made it a real POS to drive. When I had the auto trans I spent many days tuning on the Edelbrock 750 and 800 carbs without getting the stumble completely out. Backing the timing down made the biggest improvement in the stumble, but that also cost a bit of power.
I put a Street Demon 750 on last night and the stumble was gone! I can come out on the clutch at low rpm and pull off with no problems. It's incredible how much better the car is to drive now. I set the carb up with the weakest springs from the set and put the pump shot to max, bolted it on and it was like magic.

So NOW do we want to talk about how long ago I told you to get a Holley?

"IF YOU'RE UNDER CONTROL, YOU AIN'T GOING FAST ENOUGH."

Posted By: Dave440

Re: I put a Demon 750 on my stumbling 440 last night. - 08/04/14 11:39 PM

Hmmm...I'll assume you're referring to the eddy AFBs as being poorly calibrated slugs and not the AVS Thunder series. I tried to tune the stumble out of a borrowed Carter AFB comp (same as the eddy) and never got it right. Gave that thing back. Now I have an original AVS 750 and aside from needing a rebuild kit due to age...it still runs great. The eddy Thunder AVS carbs should be identical to the original with just a few improvements and more CFM (800). So to be clear...you're talking about the AFB eddys as being junk and not the Thunder series carbs right?? Cuz I was thinking about getting one.

Posted By: DaveRS23

Re: I put a Demon 750 on my stumbling 440 last night. - 08/05/14 01:53 AM

I liked the old AVSs. We have all won a lot of races with them. But they were replaced with the ThermoQuads 40+ years ago. And for good reason. The newer CarterBrocks range from poor to fair in their current configurations.

But none of them have the combination of features that the new Street Demons have. Features that have been proven to have real benefits on our engines. Often in Carter carbs. Plus the Street Demons are calibrated much, much better.

It is a former Carter engineer who has played a major role in the development of the new Street Demon. So Carter or Edelbrock could have incorporated these same improvements to their carbs. But they have not. And until they do, there are better choices out there.

Right now, when you objectively compare the features and OOTB calibration of the carbs on the market today, the new Street Demon is THE carb of choice for most of our street cars.

Posted By: Pyper70

Re: I put a Demon 750 on my stumbling 440 last night. - 08/09/14 03:13 PM

jetting, metering rods, and timing. Add on a wideband and you can tune the edelbrock. Nothing is ever OOTB on these cars. I had a 750 eddy and tuned the heck out of it...i wanted more...She sits with Dual 500 Eddy's now, both are jetted, metered, and the timing is set she needs to be. The only main difference between my setup and 95% of others on here, I run a mechanical advance MSD.

Posted By: DaveRS23

Re: I put a Demon 750 on my stumbling 440 last night. - 08/09/14 05:06 PM

The Carters and Edelbrocks have their place. But they are 60s designs that have had little or no real improvements. And we all know some versions currently being sold are nearly dysfunctional without a ton of tuning.

Just look at the basic design features that the new Street Demons incorporate. Features that have real benefits. And their calibration is very good to boot.

For true street car applications, to ignore the new Street Demon is to ignore superiority. That doesn't make the CarterBrocks junk, that just makes the Street Demons better.....for most street cars.

Posted By: BDS871Cuda

Re: I put a Demon 750 on my stumbling 440 last night. - 08/09/14 06:42 PM

Quote:

Right now, when you objectively compare the features and OOTB calibration of the carbs on the market today, the new Street Demon is THE carb of choice for most of our street cars.

I agree %100, had 3 Demon carbs all run great.
The 825 Race Demon flows over 900 cfm and worked
awesome at the track and on the street. Locked
out MSD and over .600 lift ran nice for a daily
driven street car. A new OOTB Demon is the way
to go.

Posted By: FuryBoy

Re: I put a Demon 750 on my stumbling 440 last night. - 08/10/14 03:26 AM

The new demons look great, but I have experience with an old MightyDemon and a Race Demon and an 850 VS Demon. They all ran lean. Had to run huge jets in them and over heating problems went away on a car when we swapped the Demon for a quick fuel.

I'll wait for a few more reviews before I spend money on a new street demon

I put a Demon 750 on my stumbling 440 last night.